Bring a large pot of salted water to a boil. Cook ravioli according to package instructions (approx 3-4 mins). Reserve 1/2 cup pasta water, then drain.

While water heats, melt 1 tbsp butter in a large skillet over medium heat. Sauté shallot and garlic until fragrant (2 mins).

Pour in white wine and lemon juice. Simmer for 2-3 minutes to reduce slightly.

Reduce heat to low. Stir in heavy cream. Whisk in remaining cold butter cubes a few at a time until sauce is emulsified and glossy.

Stir in lemon zest, parmesan cheese, and red pepper flakes.

Add cooked ravioli to the skillet. Toss gently to coat. Add reserved pasta water if needed to thin the sauce.

Season with salt and pepper. Garnish with fresh parsley and serve immediately.